Chimpanzees use weight to pick the best tool, and monkeys beg more when they're paid attention to, as reported in two independent research reports published July 18 in the open access journal PLoS ONE. In the chimp study, researchers found that the chimpanzees used weight to choose the best hammer to crack open nuts. Nut cracking is one of the most sophisticated instances of tool use in chimpanzees, and learning how to do it has been shown to be very difficult for some chimps.

In work led by Cornelia Schrauf of the University of Vienna, the researchers showed that the chimps were able to choose the best tool to crack nuts based solely on the weight of the tool.

Schrauf notes, "Experience clearly affected the subjects' attentiveness to the relevant tool properties. Whereas the most skilled chimpanzee showed a preference for the most efficient hammers from the early beginning of the experiment, the unskilled individuals became selective over time."

In another study, old world monkeys called Mangabeys were shown to modulate their begging behavior based on whether the experimenter was paying attention to them. The monkeys were trained to make "requesting gestures," and the researchers, led by Audrey Maille of the University of Rennes 1 in France, found that the monkeys gestured more and faster when the experimenter's body and head were facing the monkey than when they were oriented away.

The monkeys did not modulate their behavior simply based on the direction of the experimenter's gaze, though.

Maille explains, "Our study deals with...whether functional similarities may be found between human language and nonhuman primates communication. By investigating the flexibility of gestures production, we showed that old world monkeys, and not only great apes, may use communicative signals intentionally."

Do dolphins think nonlinearly?Southampton, UK (SPX) Jul 20, 2012
Research from the University of Southampton, which examines how dolphins might process their sonar signals, could provide a new system for man-made sonar to detect targets, such as sea mines, in bubbly water. When hunting prey, dolphins have been observed to blow 'bubble nets' around schools of fish, which force the fish to cluster together, making them easier for the dolphins to pick off.
... read more

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency.
All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement